The present invention relates generally to communications equipment and, more specifically, to hardware for providing wired communications connections between customers and service providers.
Presently-existing telecommunications infrastructure has been inherited from an era where customers were not offered a choice of landline service providers. Each geographic region of the United States was served by a corresponding service provider commonly referred to as a Regional Bell Operating Company, or RBOC. Accordingly, telecommunications interconnection hardware was originally designed with the assumption that all landline customers in a given geographic area would be served by the same telecommunications service provider.
More recently, the Federal Communications Commission has opened up the wired telecommunication services marketplace to free competition. This policy shift was not without its practical ramifications, the most significant of which relates to the adaptability of presently-existing interconnection hardware for use in environments where customers are offered a selection of two or more service providers. Although existing hardware may perform adequately in the operational environment of a single landline service provider, it is oftentimes woefully inadequate to meet the needs of multiple service providers. Another factor serving to further complicate interconnections between customers and multiple service providers is the current proliferation of ancillary customer premises equipment. This equipment permits the tip/ring wire pair entering the customer premises to be utilized for implementing one or more ancillary functions in addition to providing access to the public switched telephone network (PSTN) via a service provider. These ancillary functions are provided via a local service loop, and the ancillary equipment may therefore be equipped with a switching mechanism for selecting either the local loop or the PSTN loop. The local loop may be utilized for a doorbell answering system, a mass announcement system, an emergency notification system, a fire alarm notification system, a security system, or for various other purposes. Since the ancillary equipment must be placed in series (or, less commonly, in parallel) with the tip/ring lines running to the customer premises, the use of such ancillary equipment necessitates additional interconnections.
Refer to FIG. 1, which is an electrical schematic diagram showing the manner in which customers may be connected to single service providers and ancillary equipment using prior art devices and techniques. Terminal block 100 includes a set of respective first terminals 102, 104, 106, 108, each of which is connected to a corresponding second terminal 118, 120, 122, 124, through a corresponding normally-closed contact 134, 136, 138, 140. During normal operation, contacts 134, 146, 138, and 140 remain closed. However, for testing and diagnostic purposes, one or more of these contacts may be temporarily opened, for example, by introducing an insulating plug between the electrical conductors of a contact. These insulating plugs do not remain in the contacts, and are removed after testing is completed.
A service provider provides incoming telephone lines in the form of tip/ring wire pairs. A tip wire 130 of a first phone line from the service provider is connected to terminal 102 of terminal block 100, and a ring wire 132 of this first phone line is connected to terminal 104. Terminal 102 is connected to terminal 118 through a normally closed contact 134. Terminal 118 is connected to a tip wire 138 which is routed to an input port of ancillary equipment such as a doorbell answering system 170. Terminal 104 is connected to terminal 120 through a normally closed contact 136. Terminal 120 is connected to a ring wire 140 which is routed to the input port of doorbell answering system 170. A tip wire 142 and a ring wire 144 are connected to an output port of the doorbell answering system 170.
Tip wire 142 is connected to terminal 122 of terminal block 100, and ring wire 144 is connected to terminal 124 of terminal block 100. Terminal 122 is connected to terminal 106 via a normally-closed contact 138, and terminal 124 is connected to terminal 108 via a normally-closed contact. Terminal 106 is connected to a tip wire 134 routed to a customer premises, and terminal 108 is connected to a ring wire 136 routed to this customer premises.
The doorbell answering system provides a mechanism for selectively coupling tip wire 138 to tip wire 142 and ring wire 140 to ring wire 144 when access from the customer premises to the PSTN is desired. However, when it is desired to furnish a local loop to the customer premises, doorbell answering system 170 disables coupling between tip wire 138 and tip wire 142, and also between ring wire 140 and ring wire 144.
Although the interconnection topology of FIG. 1 is adequate in the operational environment of a single service provider, difficulties arise when such a topology is utilized in an environment of multiple service providers. For example, assume that a given customer uses Ameritech for PSTN access, but resides in an area where PSTN access is also offered by Bell Atlantic. The customer decides that he will discontinues his Ameritech service in favor of Bell Atlantic. To implement this change, tip wire 130 and ring wire 132, connected to an Ameritech switching office, must be physically removed from terminals 102 and 104. New tip and ring wires from a Bell Atlantic switching office must then be attached to terminals 102 and 104.
Physically removing and reconnecting wires to terminal block 100 in order to change service providers is disadvantageous. First of all, most presently available terminal blocks are not designed for repeated wire removals and reconnections. Mechanically, the terminals are designed for applications such that, once a wire is connected, it will usually remain so connected for the entire lifetime of the terminal block. With repeated wire removals and reconnections, some or all of the terminals will experience mechanical degradations over time, resulting in poor contact and imminent failure of the electrical connection. Moreover, as the quality of the connection deteriorates, its resistance to the flow of electrical current increases. This added resistance generates heat and, under some circumstances, may cause a fire. Even if a fire does not occur, repairing a broken or intermittent connection is a very arduous, labor-intensive, and time-consuming process.
Another disadvantage of physically removing and reattaching wires is that it creates the possibility of confusion. Technicians may inadvertently remove a wire from the wrong terminal, inconveniencing a customer who does not expect a disruption of service. Similarly, a technician may inadvertently connect the wrong wire to a terminal, which, depending upon what this wire is actually connected to, may totally deprives the customer of all wired telecommunications service. Moreover, as a practical matter, wiring errors are very time consuming to trace and correct in the field.
With the current and expected proliferation of telecommunication service providers, it is likely that customers will be changing service providers more frequently than in years past. Such changes will cause ever-increasing amounts of terminal block wear-and-tear. Moreover, the opportunities for wiring errors will also increase. What is needed is an improved hardware topology specifically adapted to environments where service providers may be changed on an ongoing basis.
In view of the foregoing deficiencies of the prior art, it is an object of the invention to provide a hardware mechanism for readily changing a customer""s landline telecommunications service provider.
It is a further object of the invention to provide interconnection techniques which do not require the rewiring of terminal blocks in order to change a customer""s landline telecommunications service-provider.
It is a still further object of the invention to provide interconnection techniques which do not cause unnecessary wear and tear on terminal blocks due to repeated changes in a customer""s choice of service provider.
It is yet a further object of the invention to provide interconnection techniques for use in operational environments where more than one service provider is available, and where the customer is to be provided with a local telephone loop in addition to service provider access. It is a still further object of the invention to provide interconnection techniques which enable technicians to identify wiring errors via a quick visual inspection.
In accordance with the objects of the invention, an improved terminal block is adapted to connect a customer with any one of a plurality of telecommunications service providers, so as to permit the customer""s service provider to be changed without inserting or removing wires from the terminal block.
Pursuant to a preferred embodiment of the invention, an improved terminal block includes a first connection mechanism which, when enabled, connects a customer to a first service provider, a second connection mechanism which, when enabled, connects the customer to a second service provider, and an enabling mechanism for enabling the first connection mechanism or the second connection mechanism.
Pursuant to a further embodiment of the invention, a terminal block provides a plurality of first connection mechanisms and a plurality of second connection mechanisms. Each connection mechanism includes a first normally-open contact in series between a first terminal and a second terminal, and a second normally-open contact in series between a third terminal and a fourth terminal. Each respective first connection mechanism is associated with a corresponding second connection mechanism such that the second terminal of a respective first connection mechanism is electrically connected to the first terminal of a corresponding second connection mechanism, and the fourth terminal of a respective first connection mechanism is electrically connected to the third terminal of a corresponding second connection mechanism. Each of respective pairs of first and third terminals of the first connection mechanisms are connected to corresponding incoming twisted-pair telephone lines from a first telecommunications service provider. Each of respective pairs of second and fourth terminals of the second connection mechanisms are connected to corresponding incoming twisted-pair telephone lines from a second telecommunications service provider. Each of respective pairs of second and fourth terminals of first connection mechanisms, and, consequently, each of respective pairs of first and third terminals of second connection mechanisms, are electrically connected to corresponding outgoing twisted-pair telephone lines routed to a customer premises. These telephone lines may be routed directly to the customer premises, or routed to the customer premises through optional ancillary equipment that may place switching devices in series or parallel with these telephone lines. An enabling mechanism is used to provide a conductive path across both normally-open contacts of the first connection mechanism, thereby connecting a customer with the first telecommunications service provider, or to provide a conductive path across both normally-open contacts of the second connection mechanism, thereby connecting the customer with the second telecommunications service provider. The enabling mechanism may include one or more conductive plugs that are insertable between one or more normally-open contacts.
A still further embodiment of the invention is used in the operational environment of optional ancillary equipment. Each of a plurality of first and second connection mechanisms is associated with a corresponding set of third and fourth connection mechanisms. Each third connection mechanism includes a first normally-open contact in series between a first terminal and a second terminal, and a second normally-open contact in series between a third terminal and a fourth terminal. Each fourth connection mechanism also includes a first normally-open contact in series between a first terminal and a second terminal, and a second normally-open contact in series between a third terminal and a fourth terminal. Each respective third connection mechanism is associated with a corresponding fourth connection mechanism such that the second terminal of a respective third connection mechanism is electrically connected to the first terminal of a corresponding fourth connection mechanism, and the fourth terminal of a respective third connection mechanism is electrically connected to the third terminal of a corresponding fourth connection mechanism. Each of respective pairs of first and third terminals of third connection mechanisms are connected to corresponding outgoing twisted-pair telephone lines routed to a customer premises. Each of respective pairs of second and fourth terminals of fourth connection mechanisms are connected to corresponding outgoing twisted-pair telephone lines routed to a customer premises. Each of respective pairs of second and fourth terminals of first connection mechanisms are connected to corresponding input terminals of optional ancillary equipment. Each of respective pairs of second and fourth terminals of third connection mechanisms are connected to corresponding output terminals of this optional ancillary equipment. An enabling mechanism enables the first connection mechanism and the associated third connection mechanism to provide access to the first service provider, or enables the second connection mechanism and the associated fourth connection mechanism to provide access to the first service provider. This enabling mechanism may be provided in the form of removable conductive plugs which are insertable into any of the normally-open contacts such that, upon insertion, electrical continuity between the normally-open contacts is provided.